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In a two liter flask fitted with a Dean Stark water separator and a condenser were placed 186.5 g. (0.85 mole) of benzyl oximino-acetoacetate (17), 62 g. (1 mole) of ethylene glycol, 800 ml. of benzene (reagent grade) and 2 g. of toluenesulfonic acid. The reaction mixture was boiled at reflux until 15 ml. of water was removed (3 hours). The benzene solution was washed once with saturated sodium bicarbonate solution and once with brine. After drying over anhydrous sodium sulfate, the benzene solution was evaporated, leaving 212 g. (94%) of 17 as a light yellow oil. Its NMR spectrum was consistent with the assigned structure. Generally the compound was used as such in subsequent reaction but one of the isomers can be crystallized in 35% yield from toluene-petroleum ether, m.p. 52° C. ##STR144##

1. temperatureat reflux until 15 ml
2. customof water was removed (3 hours)
3. washThe benzene solution was washed once with saturated sodium bicarbonate solution and once with brine
4. dry with materialAfter drying over anhydrous sodium sulfate
5. customthe benzene solution was evaporated
6. customleaving 212 g
7. customsuch in subsequent reaction but one of the isomers
8. customcan be crystallized in 35% yield from toluene-petroleum ether, m.p. 52° C.